diff --git a/paddle/CMakeLists.txt b/paddle/CMakeLists.txt
index 61d0aac6028474f1e105aab8cc0252376ddeadeb..4b06966fba2bc9f92756be0cb8110bbcd5272423 100644
--- a/paddle/CMakeLists.txt
+++ b/paddle/CMakeLists.txt
@@ -14,7 +14,7 @@ if(Boost_FOUND)
   add_subdirectory(memory)
   add_subdirectory(platform)
   add_subdirectory(framework)
-  add_subdirectory(op)  # because `operator` is a reserved word for CPP, so short to `op`
+  add_subdirectory(operators)
   add_subdirectory(pybind)
 endif()
 
diff --git a/paddle/framework/op_registry.h b/paddle/framework/op_registry.h
index e9e150224eeff97146d7cb305c961dd04a855fa5..61dfcb704964cd730a8fc9ab6ad394cd47cb4666 100644
--- a/paddle/framework/op_registry.h
+++ b/paddle/framework/op_registry.h
@@ -82,8 +82,6 @@ class OpProtoAndCheckerMaker {
     return op_checker_->AddAttrChecker<T>(name);
   }
 
-  void AddType(const std::string& op_type) { proto_->set_type(op_type); }
-
   void AddComment(const std::string& comment) {
     *(proto_->mutable_comment()) = comment;
   }
@@ -194,13 +192,14 @@ class OpRegisterHelper {
   static int __use_op_ptr_##op_type##_without_kernel__      \
       __attribute__((unused)) = __op_register_##op_type##_handle__()
 
-#define USE_OP_KERNEL(op_type, CPU_OR_GPU)                                     \
-  STATIC_ASSERT_GLOBAL_NAMESPACE(__use_op_kernel_##op_type##_##CPU_OR_GPU##__, \
-                                 "USE_OP_KERNEL must be in global namespace"); \
-  extern int __op_kernel_register_##op_type##_handle_##CPU_OR_GPU##__();       \
-  static int __use_op_ptr_##op_type##_##CPU_OR_GPU##_kernel__                  \
-      __attribute__((unused)) =                                                \
-          __op_kernel_register_##op_type##_handle_##CPU_OR_GPU##__()
+#define USE_OP_KERNEL(op_type, DEVICE_TYPE)                               \
+  STATIC_ASSERT_GLOBAL_NAMESPACE(                                         \
+      __use_op_kernel_##op_type##_##DEVICE_TYPE##__,                      \
+      "USE_OP_KERNEL must be in global namespace");                       \
+  extern int __op_kernel_register_##op_type##_handle_##DEVICE_TYPE##__(); \
+  static int __use_op_ptr_##op_type##_##DEVICE_TYPE##_kernel__            \
+      __attribute__((unused)) =                                           \
+          __op_kernel_register_##op_type##_handle_##DEVICE_TYPE##__()
 
 #ifdef PADDLE_ONLY_CPU
 #define USE_OP(op_type)           \
diff --git a/paddle/framework/op_registry_test.cc b/paddle/framework/op_registry_test.cc
index b3460838f9b7f02646d97a4dc75c617a03ec5c2c..9bcc0407addca555e0b47b8178f6304396ce81fc 100644
--- a/paddle/framework/op_registry_test.cc
+++ b/paddle/framework/op_registry_test.cc
@@ -19,7 +19,6 @@ class CosineOpProtoAndCheckerMaker : public OpProtoAndCheckerMaker {
     AddAttr<float>("scale", "scale of cosine op")
         .SetDefault(1.0)
         .LargerThan(0.0);
-    AddType("cos");
     AddComment("This is cos op");
   }
 };
@@ -44,7 +43,6 @@ class MyTestOpProtoAndCheckerMaker : public OpProtoAndCheckerMaker {
     };
     AddAttr<int>("test_attr", "a simple test attribute")
         .AddCustomChecker(my_checker);
-    AddType("my_test_op");
     AddComment("This is my_test op");
   }
 };
diff --git a/paddle/framework/operator_test.cc b/paddle/framework/operator_test.cc
index a033ee16617c3a328a6cd8fd682e4e76dfdfe211..204b601a4aad52ee57b81235851c9806b607799f 100644
--- a/paddle/framework/operator_test.cc
+++ b/paddle/framework/operator_test.cc
@@ -36,20 +36,6 @@ class OperatorTest : public OperatorBase {
   float x = 0;
 };
 
-class OperatorTestProtoAndCheckerMaker : public OpProtoAndCheckerMaker {
- public:
-  OperatorTestProtoAndCheckerMaker(OpProto* proto, OpAttrChecker* op_checker)
-      : OpProtoAndCheckerMaker(proto, op_checker) {
-    AddInput("input", "input of test op");
-    AddOutput("output", "output of test op");
-    AddAttr<float>("scale", "scale of cosine op")
-        .SetDefault(1.0)
-        .LargerThan(0.0);
-    AddType("test_operator");
-    AddComment("This is test op");
-  }
-};
-
 class OpKernelTestProtoAndCheckerMaker : public OpProtoAndCheckerMaker {
  public:
   OpKernelTestProtoAndCheckerMaker(OpProto* proto, OpAttrChecker* op_checker)
diff --git a/paddle/op/CMakeLists.txt b/paddle/operators/CMakeLists.txt
similarity index 100%
rename from paddle/op/CMakeLists.txt
rename to paddle/operators/CMakeLists.txt
diff --git a/paddle/op/add_op.cc b/paddle/operators/add_op.cc
similarity index 84%
rename from paddle/op/add_op.cc
rename to paddle/operators/add_op.cc
index 71fbe30289ffca3e47e04f9d0213062d5043417e..2766f0bf258ed863a4297c1e4a2be4673cbf3044 100644
--- a/paddle/op/add_op.cc
+++ b/paddle/operators/add_op.cc
@@ -1,9 +1,9 @@
 #include <paddle/framework/op_registry.h>
 #include <paddle/framework/tensor.h>
-#include <paddle/op/add_op.h>
+#include <paddle/operators/add_op.h>
 
 namespace paddle {
-namespace op {
+namespace operators {
 
 class AddOp : public framework::OperatorWithKernel {
 protected:
@@ -39,6 +39,6 @@ The equation is: Out = X + Y
 }  // namespace op
 }  // namespace paddle
 
-REGISTER_OP(add_two, paddle::op::AddOp, paddle::op::AddOpMaker);
-REGISTER_OP_CPU_KERNEL(add_two,
-                       ::paddle::op::AddKernel<::paddle::platform::CPUPlace>);
\ No newline at end of file
+REGISTER_OP(add_two, paddle::operators::AddOp, paddle::operators::AddOpMaker);
+REGISTER_OP_CPU_KERNEL(
+    add_two, ::paddle::operators::AddKernel<::paddle::platform::CPUPlace>);
\ No newline at end of file
diff --git a/paddle/op/add_op.cu b/paddle/operators/add_op.cu
similarity index 100%
rename from paddle/op/add_op.cu
rename to paddle/operators/add_op.cu
diff --git a/paddle/op/add_op.h b/paddle/operators/add_op.h
similarity index 94%
rename from paddle/op/add_op.h
rename to paddle/operators/add_op.h
index 3a5a4fb00ea8f175accdbb061d9567937b8802ec..17d459dbc86af73fa86934a5ccce9da509c59c6b 100644
--- a/paddle/op/add_op.h
+++ b/paddle/operators/add_op.h
@@ -3,7 +3,7 @@
 #include <paddle/framework/operator.h>
 
 namespace paddle {
-namespace op {
+namespace operators {
 
 template <typename Place>
 class AddKernel : public framework::OpKernel {
diff --git a/paddle/op/add_op_test.cc b/paddle/operators/add_op_test.cc
similarity index 100%
rename from paddle/op/add_op_test.cc
rename to paddle/operators/add_op_test.cc